The present invention concerns production of rubber products. More precisely, it relates to storage of uncured rubber products delivered from extrusion.
It is known that, in the non-vulcanized state, rubber presents a rather plastic state. It results that it is very difficult for this material to keep its geometric dimensions unchanged if it is stressed mechanically, for example by materials handling operations. It is thus that it is common usage to use interleaves on which the uncured rubber product to be manipulated is laid. The interleaf is constructed of a material presenting sufficient resistance to elongation. It can be rigid or flexible according to the expected utilization. In all cases, it plays the role of a holder for the uncured rubber material (whose state is plastic) and provides a grip permitting all desired manipulations.
As an illustration of the state of the art, patent application EP 0 567 147 can be cited, illustrating an interleaf used in the tire industry. The latter is shown in the form of an elongated strip, of dimensions which cannot be altered under the effect of stresses from utilization, presenting two border portions intended to protect the product stored between them on the strip. Unfortunately, when it is desired to store the product in bobbins, the proposed solution is somewhat maladapted because the border portions in question, even when cut at regular intervals, inevitably impede flexing of the said strip during winding.